Monitoring the quality of Frying Oil Blends by Different Physical Methods

Document Type : Original Article

Authors

1 Food Science and Technology Dept., Faculty of Agric., Alex. Univ., 21545, El-Shatby, Alexandria, Egypt

2 Department of Grain and Industrial Crop Technology, Faculty of Food Science, Szent Istvan University, 1118 Budapest, Villányi út 29-43.

3 Department of Physics and Control, Faculty of Food Science, Szent Istvan University, 14-16 Somloi str., 1118 Budapest, Hungary

4 Department of Refrigeration and Livestock Products Technology, Faculty of Food Science, Szent Istvan University, H-1118 Budapest, Ménesi str. 43-45.

Abstract

The repeated usage of frying oil has been proven hazardous due to the degradation process by chemical reactions that lead to changes in the quality of the oil. There are numerous analytical methods which are capable of monitoring the quality deterioration in frying oils due to their repeated heating in deep frying processes. This work explors the effect of heating on the physical behavior of soybean and rapeseed oils and their blends. Color Measurements, Electrical Impedance and Differential Scanning Calorimetry (DSC) were used for monitoring the changes in oils and their mixtures along due to the heating process. The results revealed that all methods are able to respond to the oil changes due to the heating process with different levels of accuracy. It was obvious that, colour measurements represented a high level of standard deviation, electrical impedance showed its ability to be a candidate as a rapid monitoring method; also, DSC was able to follow small changes in oils along with frying. Further tests are required to confirm the efficacy of the aforementioned methods using more oil blends to generalize the results.

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